The S8 shares the same twin-turbo V-8-engine TSFI engine with its jointly revealed siblings--the S6 and S7--but brings a full 100 extra horses to the table. It churns out 520 horsepower and 480 pound-feet of torque, which are put to use on its 4.1-second sprint to 60 mph. Top speed is electronically limited to 155 mph.

While the new engine is impressive, the performance doesn't stop under the hood. The S8 features an adaptive air suspension with variable damping, which varies ride height of the body between three levels. The steering is equally reactive, adapting its steering ratio and boost to the driving speed to provide tighter cornering. Five driving modes--comfort, auto, dynamic, individual and efficiency--allow the driver to fine-tune the ride.

The S8 sits on a spaceframe that's nearly all aluminum and rides on 20-inch S wheels rolled in 265/40-series tires. If you're not a fan of those wheels, you can choose from five options, four of which are 21-inch.

Inside, the S8 delivers on its promise of a sporty but luxurious ride with multi-way, power-adjustable comfort sport seats built exclusively for the S8, a leather sport steering wheel with contrasting stitching and aluminum-look finish shift paddles and pedals. The multimedia interface (MMI) system has an 8-inch high-res display, Bluetooth networking and touch input.

The S8 gets all the equipment options of the A8, including driver assistance systems and parking system with 360-degree camera.

We'll get a little closer to the S8 when Frankfurt gets underway on September 13. In the meantime, follow our complete coverage of the event by clicking here.